In general, a large transporter vehicle referred to as a dump truck is provided with a vessel (loading platform) capable of rising and falling on a frame of a vehicle body on which is loaded a large volume of objects (the crushed stone materials or the earth and sand, for example) as a transporting target on the vessel to transport and carry the objects in this state (Japanese Patent Laid-Open No. 2001-105956 A).
The transporter vehicle according to this type of conventional art is provided with the automotive vehicle body, which travels on wheels, the loading platform is provided on the vehicle body so as to be tiltable when the burden is loaded thereon, a hoist cylinder provided between the loading platform and the vehicle body so as to be extendable for extending to tilt the loading platform obliquely behind the vehicle body when discharging the burden from the loading platform, and a controller for controlling operation and stop of the hoist cylinder.
Then, such transporter vehicle travels to a transporting destination in a state in which the burden is loaded on the loading platform and thereafter extends the hoist cylinder to raise the loading platform obliquely backward and discharge the burden to an unloading site by the extending operation. After such discharging operation of the burden is finished, the hoist cylinder is contracted by manual operation of a control lever or contracting operation of the hoist cylinder is performed by a self-weight of the loading platform. By the contracting operation of the hoist cylinder, the loading platform falls so as to be gradually lowered to a position at which the loading platform sits on the vehicle body.